1. Field of the Invention
The present invention relates to a tension unit, and more particularly to a tension unit for a drum set pedal to remain tightened despite vibration for improved reliability.
2. Description of Related Art
With reference to FIGS. 6 and 7, a conventional drum set pedal (70) is implemented with a drum set, may be with a cymbal, drum or the like and comprises a base (71), a pedal (72), a mounting frame (73), a drive element (74) and a tension unit (75).
The base (71) is disposed adjacent to and may be attached to a percussion instrument such as a cymbal or drum and has a front end and a rear end. The pedal (72) is pivotally connected to the rear end of the base (71) and has a distal end.
The mounting frame (73) is mounted securely on the front end of the base (71) and has two stanchions (731), two mounting protrusions (732) and a rotating shaft (733). The stanchions (731) are mounted on and protrude from the front end of the base (71) parallel to each other. Each stanchion (731) has a proximal end, a distal end and an external surface. The proximal ends of the stanchions (731) are mounted on the base (71). The mounting protrusions (732) are respectively formed on and protrude from the external surfaces of the stanchions (731) near the proximal ends. The rotating shaft (733) is mounted rotatably in the distal ends of the stanchions (731), is keyed and has a connecting end and a cam. The connecting end of the rotating shaft (733) is mounted through the distal end of a corresponding stanchion (731). The cam is mounted on the connecting end of the rotating shaft (733).
The drive element (74) is attached securely to and protrudes from the rotating shaft (733) of the mounting frame (73), may be a cymbal rod or a drum hammer and has a chain (741) connecting the distal end of the pedal (72) to the drive element (74).
The tension unit (75) is mounted on a corresponding stanchion (731) and is connected to the connecting end of the rotating shaft (733) and has a threaded shaft (751), two nuts (752) and a spring (753). The threaded shaft (751) is mounted through the mounting protrusion (732) of the corresponding stanchion (731) and has a lower end, an upper end and a spring mount. The spring mount is formed in the upper end of the threaded shaft (751). The nuts (752) are mounted around and engage the threaded shaft (751) and each nut (752) has a washer (754) pressing against the mounting protrusion (732) of the corresponding stanchion (731). The spring (753) is connected to the cam of the rotating shaft (733) and the spring mount of the threaded shaft (751).
When the pedal (72) is actuated, the chain (741) rotates the rotating shaft (733) and drive element (74) so the drive element (74) sounds the cymbal or drum. Then the spring (753) provides a returning force to rotate the rotating shaft (733) and returns the pedal (72). The threaded shaft (752) can be adjusted relative to the mounting protrusion (732) of the mounting frame (73) using the nuts (752) to adjust the returning force of the spring (753).
However, when fastening the nuts (752) with the threaded shaft (751), determining when the nuts (752) are sufficiently tight is not possible so may cause over-rotation of the nuts (752) inducing excessive wear. Further, vibration caused by using the drum set pedal (70) and produced by the drum set may cause the nuts (752) to loosen and the drum set pedal (70) to malfunction, therefore causing inconvenience and unreliability to a player.
To overcome the shortcomings, the present invention provides a tension unit for a drum set beater to mitigate or obviate the aforementioned problems.